Anti-corrosive lubricating oil



United States. PatentO ANTI-CORROSIVE LUBRICATIN G OIL Ralph I.Gottshall, Willow Grove, and Raymond T. Kern, .lr., Upper MerionTownship, Montgomery County, Pa., and John G. Peters, Audubon, N. 3.,assignors to Gulf Oil Corporation, Pittsburgh, Pa., a corporation ofPennsylvania No Drawing. Application May 4, 1955, Serial No. 506,074

6 Claims. (Cl. 252-325) This invention relates to mineral oilcompositions and more particularly to mineral oil compositions adaptedto prevent rusting and corrosion of metal surfaces which are exposed tomoisture.

Simple mineral oil films afford only limited protection to metalsurfaces against rusting and other types of corrosion and, in general,can not be relied upon to provide sufficient protection against rustformation in the presence of moisture. Various lubricating compositionshave, heretofore, been disclosed for protecting metal surfaces againstrusting and corrosion but the prior compositions have not been entirelysatisfactory. It has become common practice to employ corrosioninhibitors or anticorrosion agents as additives in oil compositions forthe purpose of providing additional protection against rusting andcorrosion. Such additives have been used in various types of lubricatingcompositions such' as machine oils, internal combustion engine anddiesel lubricating oils, turbine oils, greases, etc., as well as inslushing oils and fuel oils. Some of the prior compositions haveexhibited good resistance to oxidation, but they have not given completeprotection against rusting and corrosion of metal turbine parts whichare exposed to moisture. Other compositions, while being satisfactoryfor use in the presence of relatively pure water or water vapor, do notprovide adequate protection against corrosion in the presence of saltwater.

In marine storage and use, lubricating oils frequently becomecontaminated with small amounts of sea water. When oils thuscontaminated are subsequently used, substantial corrosion of metalsurfaces with which the contaminated lubricant comes in contact may beencountered. It is desirable, therefore, to provide a lubricatingcomposition which will protect metal surfaces from salt water corrosionand which will prevent the corrosion of metal surfaces even though thecomposition may have been contaminated with salt water.

The present invention is based on a particularly effective lubricatingcomposition having good resistance to oxidation combined with goodlubricating characteristics. The compositionof the present invention hasthe further desirable properties in that it protects metal surfaces fromcorrosion and rusting normally resulting when the metal is contactedwith salt water. The improved lubricating composition of this inventionconsists essentially of.-a

homogeneous mixture of a mineral lubricating oil, an alkyl phenol, asubstantially neutral addition product of isoamyl octylacid phosphatewith a primary fatty amine containing from 8 to 18 carbon atoms, analkenyl-substituted succinic acid anhydride whereinthe alkenyl groupcontains from to 18 carbon atoms, and an acid ester of (l) a dimericacid derived from an unsaturated fatty acid containing from 6 to 22carbon atoms and having from 2"to 3 ethyleniclinkages per molecule andthe lubricating oil base or the lubricating oil base containing any oneor more but less than all of the herein disclosed constituents.

The lubricating oil to which the other constituents are added isadvantageously a highly refined paratfinic oil. By the term highlyrefined parafiinic oil we mean a petroleum lubricating oil which hasbeen refined by one of the more drastic refining methods known in theart, for example, by conventional aluminum chloride refining or by asolvent extraction adapted to remove all or substan: tially all of theunsaturated and naphthenic constituents of the oil. Aluminum chloriderefined or solvent extracted paraifinic base oil, such as a Pennsylvaniaoil provides an excellent base oil for the composition of the invention.However, drastically refined Mid-Continent and Gulf Coastal oil may alsobe used.

The alkyl phenol which is'used in accordance with the invention isadvantageously a dior tri-alkylated phenol or cresol with at least oneof the alkyl groups being a tertiary alkyl group. The alkyl groups arepreferably those containing between 3 and 12 carbon atoms. Good resultscan be obtained with a tri-tertiary butyl phenol or a ditertiary butylcresol. Examples of the preferred alkylated phenols are2,4,6-tri-tertiary-butylphenol, 2,6-di-tertiarybutyl-4-methylphenol andbis(2-hydroxy-3tertiary-butyl 5-methylphenyl)methane. The alkyl phenolscan be used in amounts of about 0.1 to about 5.0 percent by weight basedon the weight of the total composition. The preferred amount, however,is between about 0.2 and about 1.25 percent by weight. 7

The fatty amine salt of isoamyl octyl acid phosphate which can be usedin accordance with the invention is prepared by reacting isoamyl octylacid phosphate with a primary fatty amine containing from 8 to 18 carbonatoms. One example of a primary fatty amine suitable for the purpose ofthis invention is cocoamine, which is a commercially available productprepared by converting coconut oil fatty acids into the correspondingamine. It consists mostly of monolauryl amine with minor amounts ofadjacent homologues. The cocoamine salt of isoamyl octyl acid phosphateand its preparation are fully de} scribed in U. S. Patent No. 2,371,851which issued on March 20, 1945 to Herschel G. Smith and Troy L,Cantrell. 'As disclosed in said patent, the cocoamine salt of isoamyloctyl acid phosphate can be readily prepared by reacting cocoamine withisoamyl octyl acid phosphate in approximately equimolecular ratios, thereaction being so controlled as to produce substantially neutralreaction mixtures having a pH value within the range 5.5 to 7.5, asillustrated in Examples 1 and 2 of that patent. The isoamyl octyl acidphosphate employed is a di-ester of orthophosphoric acid having thefollowing formula:

This compound is "also known as 3-methylbutyl, Z-ethylhexyl acidorthophosphate. It readily reacts with cocoamine and other primary,fatty amines containing from 8 to 18 carbon atoms. Instead of cocoaminewe'can use other primary fatty amines containing from .8 vto 18 carbonatoms. These amines include, mono-capryl, CH3(CH2)8CH2NH2, mono lauryl,mono myristyl, mono-palmityl and mono-stearyl amines. The fatty acidamine'salt of isoamyl octyl acid phosphate is preferably used in anamount between'about 0.01 and about 0.2 percent by weight based on theweight of the total com position. However, improved results can beobtained with an amount between about 0.001 and about 1.0 percent byweight.

The alkenyl-substituted succinic acid anhydridecan'be copolymers mayalso be formed. The alkenyl chain may contain from 5 to 18 or even morecarbon atoms. The acid anhydrides. having an alkenyl group containing atleast six carbon atoms are particularly advantageous. The especiallypreferred acid anhydrides are those in which. the alkenyl substituentcontains a relatively large number of. carbon atoms, for example, 8 to12 carbon atoms. In. illustrating the composition of the invention, wehave used a commercially available material, dodecenyl succinicanhydride, obtained from National Aniline Division, Allied Chemical &Dye Corporation. The. alkenyl-succinic acid anhydride can be used inamounts of about 0.01 to about 0.3 percent by weight based on the weightof the total composition. Although some improvement in the rustinhibiting properties of the oil is obtained with increasingconcentrations of alkenyl succinic acid anhydride, amounts in excess of0.3 weight percent are, in general, undesirable because of theundesirably high neutralization value which the greater amount of. acidanhydride imparts to the oil.

The acid esters employed in accordance with this invention are thereaction products resulting from the esterification of a dimerizedunsaturated fatty acid with a partial fatty acid ester of an alkitolanhydride. The ratio of reactants may range from one mol of dimerizedacid per mol of partial fatty acid ester up to the number of mols ofdimerized acid that is equal to the number of free hydroxyl groups inthe partial fatty acid ester, per mol of partial fatty acid ester.

The esterification reaction is effected in conventional manner and underconventional conditions. Thus, while esterification may proceed slowlyat room temperature, the reaction is normally advantageously acceleratedby heating the reactants, usually with refluxing, and/ or by the use ofconventional esterification catalysts, such as hydrogen chloride,sulfuric acid, or an aromatic sulfonic acid, such as p-toluene-sulfonicacid. The reaction may bedriven to substantial completion by removingone of the products of reaction. Since the herein disclosed dimericunsaturated fatty acids, partial esters of. alkitol anhydrides, andtheir reaction products boil at a temperature substantially above theboiling point of water, the reaction conveniently may be driven tocompletion by removal of the water of esterification by distillation.The removal of water from the reaction mixture may be facilitated bymechanical agitation, or by bubbling an inert gas, such as nitrogen,through the reaction mixture.

By way of illustrating the foregoing process, one, two or three mols ofdimerized acid may be esterified with one mol of .a partial fatty acidester containing three free hydroxyl groups, under conventional reactioncon ditions,,with the elimination, respectively, of one, two or threemols of water of esterification, to form, respectively, a mono-, .diortri-acid or tricarboxylic ester of the dimerizedacidand the partialfatty acid ester.

If desired, the, reaction products may be prepared by eifectingesterification of the reactants in mineral oil solution. This expedientis advantageous in that it prevents localized overheating of thereactants. Moreover, the resulting-reaction products are in the form ofmineral oil. concentrates, the use of which often facilitatessolution-offlle additives in their ultimate vehicles.

.Theadimerized acids referred to above are dimers, i. e'., bimolecularaddition products of conjugated or uncon jugatedrdienoic oritrienoicfatty acids having from 6 to 22 carbon atoms beforedimerization. Dimeric acids derived from dienoic and trienoic fattyacids are well known and can be prepared by conventional methods whichform no part of this invention.

More particularly, dimerized acids capable of forming the compoundsutilized in the composition of this invention are prepared from dienoicor trienoic fatty acids having the generic formula CnHzn-mCOOl-I, wheren is an integer of from 5 to 21 and x is 3 or 5. As will be evident,such monomeric acids contain from 6 to 22 carbon atoms and may contain 2or 3 ethylenic linkages as the ratio of carbon to hydrogen increases, i.e.', as): increases from 3 to 5. Dimerized acids corresponding to theaddition products of the foregoing acids therefore may be defined by thegeneric formula:

0 I i-OH Cn EIEn-z Tl-OH A where n is an integer of from 10 to 42 andwhere x is an even integer of from 6 to 10. These dimeric acids aretherefore dibasic or dicarboxylic acids having from 12 to 44 carbonatoms.

Representative members of the class of dimerized acids capable offorming the compounds employed in the compositions of this invention aredimers of dienoic acids such as sorbic (hexadienoic), linoleic(octadecadienoic), humoceric (nonadecadienoic) and eicosinic(eicosadienoic) acids. Dimers of trienoic acids, for example, linolenicand eleostearic (octadecatrienoic) acids may also be used.

It is not necessary that both of the unsaturated fatty acid molecules ofthe bimolecular addition product be identical. Dimers of mixed.composition such as those obtained by dimerizing mixed dienoic, mixedtrienoic or mixed dienoic and trienoic acids such as may be derived fromcertain naturally occurring drying oils, e. g., linseed oil and soybeanoil, are quite satisfactory.

Dienoic and trienoic acids having 18 carbon atoms, especially thosehaving conjugated olefinic linkages, are preferred for reasons ofeconomy of procurement, ease of reaction and the general excellence ofthe additives prepared therefrom.

The partial esters of alkitol anhydrides and fatty acids adapted for usein the formation of the reaction products are those resulting fromesterification with the desired fatty acid of at least one, but lessthan all, of the available hydroxyl groups of an alkitol anhydride. Byalkitol anhydride is meant an intramolecular, monoor dian- .hydride of apolyhydric alcohol which contains at least 4 carbon atoms and at least 4hydroxyl groups, or mixtures of said anhydrides. Representative of theclass of alkitols are erythritol; pentitols, such as arabitol, xylitoland adonitol; and hexitols such as mannitol, dulcitol and sorbitol, justas the xylitans and sorbitans are representative of the alkitolanhydrides, -or alkitans.

Fatty acids capable of forming partial. esters of.alkitol anhydridessuited to the preparation of the additives utilized in this inventionare the fatty acids containing from. 12 to 24 carbon atoms. These acidsmay be saturated or unsaturated, and they may be substituted with groupswhich do not adversely affect the oil-solubility or corrosion-inhibitingproperties of the final reaction product. Representative of this groupof acids are lauric acid, oleic acid, ricinoleic acid, stearic acid andlignostearic acid.

Partial esters capable of reacting to form the. reaction productsinclude those formed by reacting a fatty acid of the foregoing kind withthe desired alkitol anhydride in a molar ratio of at least 1:1, but lessthan that which would result in neutralization of all of the hydroxylgroups of-thealkitol anhydride; 'The used mixtures of partial fatty acidesters of alkit ol' anhydridesis also included within the scope of theinvention. Specific examples of partial esters of alkitol anhydridescapable of reacting with dimeric unsaturated fatty acids to form acidesters which can be used in the composition of the invention are xylitanand sorbitan mono-, sesqui-, diand trioleates and stearates. Partialesters of hexitol anhydrides, i. e., anhydrides of polyhydric alcoholscontaining 6 carbon atoms and 6 hydroxyl groups, are preferred.

The partial esters ofalkitol anhydrides disclosed herein as well as themethod of preparing the same are conventional and form no part of thepresent invention. Accordingly, they need not-be described in detail.

Representative specific examples of acid esters of dimeric acids withpartial fatty acid esters of alkitans which can be used in thecompositions of this invention are the monoand polycarboxylic acidesters of dimerized linoleic, linolenic and eleostearic acids withsorbitan and xylitan mono-, se'squi-,'-di-' and tri-oleates andstearates. Included within the foregoing representative class ofcompounds are mono-, di-, and triacid dilinoleic mono-, di-' andtriesters of sorbitan monooleate, monoand diacid dilinoleic monoanddi-esters of sorbitan dioleate, monoacid dilinoleic mono-esters ofsorbitan trioleate, monoand diacid dilinoleic monoand -diesters ofxylitan monooleate, mono-acid dilinoleic mono-esters of xylitandioleate, and corresponding acid esters made from dimerized linolenicand eleostearic acids, as well as those made from partial esters ofstearic acid.

The preparation of the class -of compounds useful in the compositions ofthe invention can be further illustrated by the following specificexample:

EXAMPLE I An acid ester of a 'dimeric unsaturated fatty acid and apartial fatty acid ester of an alkitol anhydride was prepared byadmixture and reaction of 428 parts by weight of sorbitan monooleate(manufactured by the Atlas Powder Company of Wilmington, Delaware, andmarketed under the name Span 80) with 560 parts by weight of dimerizedlinoleic acid (manufactured by Emery Industries, Inc. of Cincinnati,Ohio, and marketed under the name of Emery 955 Dimer Acid). The reactionmixture was heated under reflux, until 18 parts by weight of water hadbeen trapped off, the maximum temperature reached by the reactionmixture being 500 F. The dimerizedli noleic acid of this example had thefollowing characteristics! V t v Straw-colored Physical state: Viscousliquid Molecular weight (approx.) 564 Gravity: API 13.0 Viscosity, SUS200- F 597 Flash, C: F 510 Fire, 0 Cz F 575 Color, NPA +10 Iodine No.,mod. Hanusu 83.3 Saponification No 186 Neutralization No 182Dimer-content... (approx.) 85 Trimer and higher (approx.) 12 Monomer(approx) 3 The properties of the sorbitan monooleate were as follows: 5

Pour: F +10 Physical state, room temp viscous liquid Color, ASTM union4.5 Water by distn: percent nil Carbon residue, conradson: percent 2.94Neutralization value, ASTM D974-51T,

total acid No 6.15 pH value, glass-calomel electrodes 7.0 SaponificationNo., ASTM D9448T 149.0 Acetyl value, Gulf 433 142 Ash: percent 0.212

The product obtained in the above-described reaction was a clear,viscous liquid containing predominantly mono-acid esters of dimerizedlinoleic acid and sorbitan monooleate, having the following physicalproperties:

The acid esters of otherdimerized unsaturated fatty acids and otherpartial fatty acid esters of alkitol anhydrides are similarly prepared.

The amount of the acid ester employed in the composition of theinvention depends upon the characteristic of the base oil as Well asupon the amounts of other additive agents present. Satisfactory resultscan be obtained when the amount of acid ester comprises about 0.001 toabout 1.0percent by weight based on the weight of the total composition.A preferred range, however, comprises about 0.01 to about 0.2 percent byweight.

The lubricating oil compositions of this invention can contain other.additive agents if desired to improve other specific properties withoutdeleteriously affecting the beneficial properties of the compositions.For example, pour point depressors, viscosity and viscosity indeximprovers, dyes, sludge inhibitors and the likecan be used. Also, ifdesired, the oil can contain a foam inhibitor such as organo-siliconoxide condensation products, organosilicol condensation products and thelike.

The individual constituents of the composition of this invention may beadded to the lubricating oil base in any order or simultaneously eitherper se or in the form of a mineral oil concentrate. The latter practiceis sometimes desirable in order to facilitate compounding of thecomposition.- When a concentrate is prepared, it advantageously containsabout 50 percent by weight of a mineral oil solvent. However, suitableconcentrates can be prepared in which the mineral oil solvent comprisesfrom 30 to percent by weight of the total concentrate. Thus, a valuableoil benefiting concentrate can be formed byadrnixing the hereindisclosed constituents with a ,mineral oil solvent. In some instances,the oil to be improved may already contain an antioxidant such as analkylated phenol. Thus, where the oil contains an alkyl phenolantioxidant, the concentrate'will require no alkyl phenol. Theconcentrate can, of course, contain other I inhibitors and the like.

fiting-concentrates will consist of about 30 to about 70.450.15...percent by weight of amineral oihabout 20. to,about.4.0

percent by weight of dodecenyl succinic anhydride, about 10 .to about 30percent by weight of the esterification product of sorbitan monooleateand dimerized linoleic acid, and about to about 25 percent .by Weight ofcoco- It will be noted from the data in TableI that the base oil,composition A, gave no protection against rusting when the test bar wassubjected to procedure B .of ASTM .D665-53T. As will be further notedfrom .com-

amine isoamyl octyl orthophosphate. 5 positions B, C and D, severerusting occurred when the One embodiment .of an oil benefitingconcentrate, .acoil contained 1.25 percent of 2,6-diatertiary-butyl-4rnethcording to this invention, for use in an oil already ccnylphenoland up to 0.1 percent of dodecenyl succinic antaining an alkylatedphenol consists of about 30 percent y AS The dodecenyl .SuCCiIiiCsanhydfide was by weight of dodecenyl succinic anhydride, 20 percent bycreased in compositions .E and F the amount of rusting Weight ofdimerized linoleic acid-sorbitan monooleate decreased; however, theneutralization value of the oil acide ester reaction product, 11 percentby weight of increased to an undesirable level. When cocoamineisococoamine isoamyl octyl orthophosphate and 39 percent amyl octylorthophosphate and the dimerized .linoleic by weight of a minerallubricating oil solvent. acid sorbitan monooleate acid ester reactionproduct were A suitable mineral oil solvent has the following typicaladded to the base oil containing 2,6-di-tertiary-butyl-4- properties. 15methylphenol the composition (composition G) had improved rustinhibiting characteristics over "the base oil y, APT but rusting was notcompletely eliminated. It will be Viscosity, SUS: noted from compositionH, which illustrates a compo- 100 F 205 sition'of the invention, thatthe rusting was completely 210 F V 4.6.8 eliminated even though thecocoamine isoamyl octyl or- Vi ity index --1- 98 thophosphate, thedimerized linoleic acid-sorbitan mono- Fash Po 0C3 oleate acid, and thedodecenyl succinic anhydride were Fire p F --.--,.-.,-u 420 present inamounts less than had been used when testing P rp n .-.s-s-. 1 5 theindividual constituents. The strikingly superior re- ASTM n Qn-.-.-.-.-2.25 sults .obtained with the combination of additives are un-Nelltfalization value, ASTM D974-53T 0.02 expected in view of theresults obtained with the additives individually. It is thus apparentthat the additives The advantages obtained when using the improved areacting cooperatively in giving a result which is greater lubricatingcomposition of the invention as compared than the sum of theirrespective properties. with the base oil and the base oil containingless than Compositions G and H were prepared by incorporating all of theaddition agents are illustrated by the followan oil benefitingconcentrate into the base oil to which ing specific examples. In theseexamples, theimproved 1.25 percent of ,2,6,-di-tertiary-butyl-4-methylphenol had rust inhibiting properties ofthe lubricating composition previously been added.. The oil benefitingconcentrate have been demonstrated .by subjecting the various oil usedto prepare composition G consisted of about 30 compositions to ASTM testfor rust-preventing ch'aracpercent by weight .of the esterificationproduct of sorbiteristics of steam-turbine oil in the presence of water,tan monoolea'te and dimerized linoleic acid, 20 percent D665-53T,procedure B. In brief, the test involves placby weight of cocoamineisoamyl octyl orthophosphate and ing a 300 milliliter sample of the oilin a 400 milliliter 50 percent by weight of a mineral lubricating oilhaving beaker which is, in turn, immersed in a constant teman APIgravity of about 30 and a viscosity of about 205 perature bathmaintained at a temperature of 140 F. 40 SUS at 100 F. The beaker isfitted with a cover provided with openings In preparing composition H,an oil benefiting confora stainless steel motor-driven stirrer, and forinsercentrate was first prepared by admixing 30 percent by tion of astandard steel test bar which has been carefully Weight of dodecenylsuccinic anhydride, 20 percent by cleaned and polished according toprocedure prescribed weight of the esterification product of sorbitanmonoby the ASTM test. The stirrer is started and when the oleate anddimerized linoleic acid, 11 percent 'by eight oil sample in the beakerreaches a temperature of 140 of cocoamine isoamyl octyl orthophosohateand 39 per- F., the test bar is lowered through the proper opening centby weight of a mineral lubricating oil having an and is suspended fromthe beaker cover. After '30 min- API gravity of about 30 and a viscosityof about 205 utes, 30 milliliters of synthetic sea water is introducedSUS at 100 F. into the bottom of the beaker. Stirring is then contin Themake-up and properties of a typical oil benefitued for 24 hours with thetemperature maintained at ing concentrate of the invention are given inTable H. 140 F. At the end of this period, the steel bar is removed andexamined for rust spots. v Table In making the comparative tests a baseoil having an API gravity of 32.7 was used. This oil had a viscosityComposition, percent by weight: of about 153 SUS at 100 F. The oil ineach instance Cocoamine isoamyl octyl orthophosphate 8.9 also containedabout 0.0001 percent by weight of Dow- Dimerized linoleic acid-sorbitanmonooleate Corning Silicone Fluid 200 as a foam inhibitor. esterreaction product of Example I 13.3 The results obtained in the foregoingtest are presented Dodecenyl succinic anhydride 27.8 in Table I.Paraflinic mineral oil (ZOO/2.5) 50.0

Tablel Composition, Percent by Weight A B O D E F G H Base 011 100 98.7398.70 98. 98.55 98.45 98.65 98.68 26-di-tertlary-butyl4-methylphenol.1.25 1.26 1.2 1.25 1.25 1. 25 1.25

ocoamine isoamyl octyl orthoph p e 0.02 0.01 Dimerized linoleicacid-sorbitan monooleate acid ester reaction product of Examplel 0.080.02 Dodeceuylsucciuic anhydrtde 0.02 0.05 0.1 0.2 0.3 0.04 Inspection:I v

ASTM D 665-523 T Proce'dure B,

Percent Rust... 100 100 100 25 15 40 0 Neutralization Value ASTM D 7Table -Il.Continued Inspection:

Gravity: API 21.3 Viscosity, SUS:

210 F 59.4 Viscosity index 86 Flash point, C, F 360 Fire point, 0C, F400 Pour point, F +5 Color, ASTM union 3.25 Neutralization value ASTMD974-53T 84.0

Saponification No. ASTM D94-52T 140.9

That the properties of the base oil to which an oil benefitingconcentrate of this invention has been added are not deleteriouslyaffected can be shown by compar ing the properties of composition A withcomposition H. The properties of these composition-s are given in TableIII.

The improved characteristics of a composition of the invention,composition H, over the characteristics of the base oil, composition A,are shown in Table IV. The film tenacity test reported in the table,like the other rust preventive tests, is designed to evaluate corrosionresistance of the film of the oil composition as applied to steelsurfaces. It is carried out immediately after the ASTM D665-47T,procedure A. If the steel bar used in the ASTM test shows no evidence ofrusting, it is suspended in the mouth of a 300 milliliter flask and isallowed to drain. The beaker containing the oil sample is removed fromthe constant temperature bath and is replaced with a clean beakercontaining 300 milliliters of distilled water. With the stirreroperating, the temperature of the water in the beaker is allowed toreach 140 F. When the test bar has drained for a period of 30 minutes,it is inserted in the beaker as above. Stirring is continued for 24hours, after which the test bar is removed and examined for rust spots.

It will be seen that this test is quite drastic, since throughout itsoperation the steel test bar is protected from the rust only by a thinresidual film of the oil being tested. It not only evaluates theprotection against rusting provided by the composition, but alsoindicates the tenacity with which a film of the composition adheres tothe metal surface.

Table IV Properties Composition Composition Rug tglreventive Test ASTM D665- Procedure A Steel Rod: Appearance rusted bright-passes. AreaRusted: Percent 100 0. Film Tenacity Test, 24 hr:-

Steel Rod: Appearance; bright-passes. Area Rusted: Percent 100 0.Procedure B Steel Rod: Appearance rusted bright-passes. Area Rusted:Percent 100 0. Neutralization Value ASTM D 974- 53T 0.02-- 0.15.Oxidation Test ASTM D 943-47 T:

After 1,000 hrs. Oxidation, Appearcompletely bright-passes.

ance of Coil. rusted. Hours to give 2.0 Acid No 240 2,460.

It will be noted from the data in the above table that composition H hasstrikingly superior properties not only with respect to rust protectionbut also with respect to oxidation stability.

The conditions of ASTM D943-47T are such as to approximate theconditions to which a lubricating oil is subjected in circulatinglubricating systems of large capacity wherein the lubricant becomescontaminated with water. Briefly, the test comprises subjecting 300milliliters of the lubricating oil sample to a flowing stream of oxygenin the presence of 60 milliliters of water and an iron-copper catalystand determining the time required for the acidic oil oxidation productsto build up to a neutralization value (acid number) of 2.0. The flow ofoxygen is maintained at 3 liters per hour. It has been recognized in theart that lubricating oils in which the amount of acidic organicoxidation products is greater than that represented by an acid number of2.0 are no longer serviceable because of corrosivity, the formation ofsludge and stable emulsions and the general deterioration'of lubricatingqualities.

It is to be noted that during the course of the test, the flowing streamof oxygen intimately mixes the oil and water layers, thus resembling theconditions encountered in lubricating steam turbines, paper mill rolls,etc. The iron and copper catalyst metals represent the metals normallyfound in industrial machinery and simulate the catalytic deterioratinginfluences of these metals on the oil in the presence of water andoxygen. The increased length of time required before composition H givesan acid number of 2.0 is indicative of the superior properties of acomposition of the invention.

While the invention has been described above with reference to certainspecific embodiments thereof by way of illustration, it is to beunderstood that the invention is not limited to such embodiments exceptas hereinafter defined in the appended claims.

We claim:

1. An improved lubricating composition consisting essentially of a majorproportion of a mineral lubricating oil and minor proportions consistingof about 0.1 to about 5.0 percent by weight of an alkyl phenol, saidalkyl phenol containing at least one alkyl group containing between 3and 12 carbon atoms, about 0.001 to about 1.0 percent by weightof asubstantially neutral addition product of 3-methylbutyl,Z-ethylhexylacid orthophosphate and a primary fatty amine, said amine being amono-alkyl amine containing from 8 to 18 carbon atoms, about 0.01 toabout 0.3 percent by weight of an alkenyl-substituted succinic acidanhydride wherein the alkenyl group contains from 5 to 18 carbon atoms,and about 0.001 to about 1.0 percent by weight of an acid ester of (l) adimeric acid derived from an unsaturated fatty acid containing 18 carbonatoms and having from 2 to 3 ethylenic linkages per molecule and (2) apartial ester of a fatty acid containing 18 carbon atoms and a hexitolanhydride.

2. An improved lubricating composition consisting essentially of a majorproportion of a mineral lubricating oil and minor proportions consistingof about 0.1 to about 5.0 percent by weight of an alkyl phenol, saidalkyl phenol containing at least one alkyl group containing between 3and 12 carbon atoms, about 0.001 to about 1.0 percent by weight of thecocoamine salt of 3-methylbuytl, 2-ethylhexyl acid orthophosphate, about0.01 to about 0.3 percent by Weight of an alkenyl-substituted succinicacid anhydride wherein the alkenyl group contains from 8 to 12 carbonatoms, and about 0.001 to about 1.0 percent by weight of an acid esterof (1) a dimeric acid derived from an unsaturated fatty acid containing18 carbon atoms and having from 2 to 3 ethylenic linkages per moleculeand (2) a partial ester of a fatty acid containing 18 carbon atoms and ahexitol anhydride.

3. An improved lubricating composition consisting essentially of a majorproportion of a mineral lubricating oil and minor proportions consistingof about 0.1 to about 5.0 percent by weight of a tertiary alkyl phenol,said tertiary alkyl phenol containing at least one. alkyl groupcontaining between 3 and 12.c arbon atoms, about r00l to about 1.0percent by weight of the cocoamine salt of 3-methylbutyl,2-ethylhexylacid orthophosphate, about 0.01 to about 0.3 percent by weight ofdodecenyl succinic anhydride, and about 0.001 to about 1.0 percent byweight of an acid ester of a dimer of linoleic acid and sorbitanmonooleate.

' 41. An improved lubricating composition consisting essentially of amajor proportion of a mineral lubricating oil and minor proportionsconsisting of about 0.1 to about 5.0 percent by weight of2,6-di-tertiary-butyl-4- methylphenol, about 0.001 to about 1.0 percentby Weight of the cocoamine salt of 3-methy1butyl,2-ethylhexyl acidorthophosphate, about 0.01 to about 0.3 percent by weight of dodecenylsuccinic anhydride, and about 0.001 to about 1.0 percent by weight of anacid ester of a dimer of linoleic acid and sorbitan monooleate.

5. An oil benefiting concentrate consisting of about 30 to about 70percent by weight of a mineral oil, about 20 12 to about 40 percent byweight of dodecenyl succinic anhydride, about 10 to about 30 percent byweight of the esterification product of sorbitan monooleate anddimerized linoleic acid, and about 5 to about/ percent by weight ofcocoamine isoamyl octyl orthophosphate.

6. An oil benefiting concentrate consisting of about 39 percent byweight of a mineral oil, about'30 percent by weight of dodecenylsuccinic anhydride, about 20 percent by weight of the esterificationproduct of sorbitan monooleate and dimerized linoleic acid, and about 11percent by weight of cocoarnine isoamyl octyl orthophosphate. 7

References Cited in the file of this patent UNITED STATES PATENTS2,371,656 Smith et al- Mar. 20, 1945 2,398,193 Sharp Apr. 9, 19462,442,672 Fuchs et a1 June 1, 1948 2,631,979 McDermott Mar. 17, 19532,715,108 Francis Aug. 19, 1955

1. AN IMPROVED LUBRICATING COMPOSITION CONSISTING ESSENTIALLY OF A MAJORPROPORTION OF A MINERAL LUBRICATING OIL AND MINOR PROPORTIONS CONSISTINGOF ABOUT 0.1 TO ABOUT 5.0 PERCENT BY WEIGHT OF AN ALKYL PHENOL, SAIDALKYL PHENOL CONTAINING AT LEAST ONE ALKYL GROUP CONTAINING BETWEEN 3AND 12 CARBON ATOMS, ABOUT 0.001 TO ABOUT 1.0 PERCENT BY WEIGHT OF ASUBSTANTIALLY NEUTRAL ADDITION PRODUCT OF 3-METHYLBUTYL,2-ETHYLHEXYLACID ORTHOPHOSPHATE AND A PRIMARY FATTY AMINE, SAID AMINE BEING AMONO-ALKYL AMINE CONTAINING FROM 8 TO 18 CARBON ATOMS, ABOUT 0.01 TOABOUT 0.3 PERCENT BY WEIGHT OF AN ALKENYL-SUBSTITUTED SUCCINIC ACIDANHYDRIDE WHEREIN THE ALKENYL GROUP CONTAINS FROM 5 TO 18 CARBON ATOMS,AND ABOUT 0.001 TO ABOUT 1.0 PERCENT BY WEIGHT OF AN ACID ESTER OF (1) ADIMERIC ACID DERIVED FROM AN UNSATURATED FATTY ACID CONTAINING 18 CARBONATOMS AND HAVING FROM 2 TO 3 ETHYLENIC LINKAGES PER MOLECULE AND (2) APARTIAL ESTER OF A FATTY ACID CONTAINING 18 CARBON ATOMS AND A HEXITOLANHYDRIDE.